There's obviously quite a difference in scale between a 5kg battery bank and a diesel generator. Something like this could easily fit into a backpack and could be quite useful for a small photography/drone team for instance. Enough power for cameras and small electronics when you're away from roads.
A lead acid battery with 73lbs and can be transported by your car. This weighs 12lbs.
I do think this is going to fit an extremely niche market. Where are you going to go away from an outlet that requires you to charge your phone 47 times? If you're out backpacking in the wilderness and you've already used 12lbs of weight for this thing, you don't have enough food for 47 days.
I guess it makes sense if you want to get some drone footage on your backpacking trip or need a laptop / satellite phone for some government survey.
Either way, send like you would be better off with wise and financially by buying multiple chargers and distributing then between several people than this $700 monstrosity.
I dont know where you came up with 73 lbs. 100Wh (12V, 9Ah) lead-acid battery has cca 5 lbs. You would need 4-5 of those + inverter. That makes around 25-30lbs. Definitely not 73.
This battery pack is definitely not for backpacking - it is way too heavy. Even considering its capacity it is too heavy (only 85Wh/kg, Li-ion batteries have around 250Wh/kg so the whole pack should have above 150Wh/kg).
The problem with lead acid batteries is that in higher drain instances like charging laptops, the true total capacity is not going to be 9Ah. While li-ion batteries do well if discharged to 20% all the time, lead acid will quickly wear out if discharged to 20% frequently!
Car batteries are not designed to be completely discharged and recharged. They're meant to start your car then get topped off by the alternator. But yeah, you can get a deep cycle SLA battery instead, and probably cheaper.
What does CPAP refer to? Google says "Continuous positive airway pressure" which refers to sleep therapy. Pretty sure that's not related to what you mean. :D
CPAP machines help with sleep apnea, which can be very serious for some people. Having a device that can run a CPAP machine if the power goes out is important, especially if you live in an area where power outages are frequent. Devices like this are far easier to keep ready and use than a generator.
And what if you couldn’t afford fancy medical device, because your health insurance wouldn’t cover it or you live in a 3rd world country? Better live without one at all?
Thats what he means... CPAP is a machine that help people with sleep apnea breath noramlly while sleeping. It looks like an oxygen mask hooked up to your face and obviously needs to have a VERY RELIABLE source of power. Thus the niche case use for this is for CPAP machine users as a backup incase of a power outage. A typical APC desktop UPS will only provide power for about an hour while this would run all night.
I was thinking the same thing. Shame it doesn't support jumpstarting. It's also unfortunate it doesn't seem to have any sort of water resistance rating, basically eliminating it from being safely used outdoors, especially if camping.
I've jump-started a car off my R/C shortcourse truck battery. It's a cheap $25 5000mah 11.1v nominal (peak is well above the 12v necessary to crank a starter motor) and it's the size of a pack of cigarettes. The catch is it is rated at 50C; it can output 50x its rated capacity in a burst. Even cheap LiPo packs are rated at 25C which supplies the 125amps to jump-start a car on a mildly dead battery. These packs usually charge at 5C but good packs can charge at 10C (which means they can recharge in a few minutes from a capable charger.)
You need to understand the underlying chemistry used here. Lithium Ion, Polymer and even tiny LiFE cells can all jump-start a vehicle as is if they have the required discharge rating.
That said, even if they didn't want to use capable quality cells (which they SHOULD for $700!) they could use an amplifier in the form of a super capacitor or a separate low amp trio of lithium cells to supply the necessary current to turn over an engine. I think this is a very useful feature, especially for a device like this.
"The ChargeTech PS120K packs multiple batteries for a total capacity of 124,800 mAh (462 Wh), which is enough to charge a typical 13.3-inch laptop for 10 times, or Apple’s iPhone XR 47 times"
Back of the napkin math doesn't really apply well. Not only will the 124800mAh pack only charge the 2942mAh iPhone XR battery just 42.5 time but also the battery capacity is lower the higher the discharge current. And lithium batteries are notoriously bad at this. You can easily lose 20-25% of the capacity just by increasing the discharge current.
The C value (Capability, the higher it is, the more current you can draw without significantly lowering its capacity) is much better for a lead acid battery, at the downside of about twice the weight.
So for people taking it to charge their phone 45 times it may work better than for those who assume they can power a lot of devices at the same time using the same math. This should be good to know for people to properly adjust their expectation to the use case.
Huh? That's not how the C rate works. C is the capacity of the battery (any battery type). With most batteries, it is advisable to not charge them at a current larger than 1 C, for longevity sake. It is also advisable to not discharge them at unreasonable C rates. Many new lithium batteries are designed for certain tasks (car starter battery, drone flying) where high C-rate discharge is important, so they come with 30C, 50C, 100C ratings. Some people also don't want to wait a long time to recharge their battery, so they are fine at charging at 5C for a reduced cycle life. If a 50C batteries get discharged in a drone and lands when the drone indicates it only has 3.1V left (3.0V is generally the level at which you want to stop draining your lithium battery, non-standard chemistry not withstanding), it can easily get back up to 3.7V when you apply a simple 500mA discharge current to charge your phone (let's say this is a 5000mAh battery, so a 0.1C discharge rate). But try using it for a 10C application it won't let you until you recharge it again (the voltage will collapse immediately). Lead acid batteries are just as general as lithium ones. You have car batteries which have huge amperage (C-rate in your example), but really bad deep discharge functionality. And then you have ones that are used in UPSes that offer fine discharge rates (less than car batteries) but great deep cycle stability. It's not at all how you describe it, unfortunately. This is why capacitors are the future of electric mobility, not batteries. But that's beside the point. :D
I thought I was pretty clear about what I meant. Let's keep it simple this time: a battery will have lower capacity the faster you discharge it (the higher the C rate, the lower the energy and capacity). I'm not talking about exceeding load limits. I'll let the experts speak now:
"The available capacity of a battery depends upon the rate at which it is discharged."
"A battery rated at 100 Ah will deliver 5 A over a 20 hour period at room temperature. However, if it is instead discharged at 50 A, it will run out of charge before the theoretically-expected 2 hours."
I tested this myself with my regular RAV Power and Anker powerbanks (all under ~30000mAh) although I didn't really need to validate physics. The capacity was 10% lower with 2.4A vs. 1A discharge. And this is while starting with ~65-75% usable capacity anyway. It appears that the increase in temperature and thus in voltage does not compensate for the increase in resistance.
Since the battery in the article is obviously meant for heavy duty use, not charging one phone, these figures would have been relevant. I'm willing to bet this doesn't actually go over 100000mAh and will be less than that when discharging it rapidly (perhaps no more than 80000mAh).
meh, i built my own 600wh battery yesterday for £40, using some recycled broken laptop batteries. took 3.5h to build. $700 for one sounds crazy after that XD
The advertising picture notes "MAH", which would clearly mean mega-amp hours, not milli-amp hours. SI prefixes are very case sensitive. Also, this whole amp-hour marketing makes no sense, because it's based on a voltage of 3.7. We need to get away from it. Way away from it. Wh is what we need, at least.
No, if we're using mAh then people really want the numbers to be comparable. I've already seen a tablet with a 7.4v battery double its mAh to make a "3.7v equivalent" number. If they were using watt-hours, they wouldn't have had to do anything special.
Especially considering this kind of equipment: Usually we use 12v car batteries to make portable power sources with inverters, and this box has the same 400-500 Wh despite the huge mAh number.
13S3P internal battery made with 3200mAh rated cells, probably LG INR18650-MH1, Panasonic NCR18650BM or Samsung INR18650-32A, or maybe some other higher capacity cells if the fellow ChargeTech designers are rigorously honest and like to err on the safeside as cell typical ratings usually are about best case scenarios. Actual internal battery capacity thus should be 3200mAh × 3 = 9600mAh, for a 3.7V × 13 = 48.1V or ≈48V nominal figure. This fits well with the likely being used 48V AC inverter. 124800mAh marketing gimmick. Capacity means really nothing here, like torque or rpm when talking about motors. Capacity times voltage is energy, 462Wh 0.2C typical in this case, which by the way you won't see at the outputs because of DC/DC and DC/AC conversion losses.
You'd be right if engine manufacturers would use gimmicks like stating numbers that are relative to some "reference" engine or component, not the actual one being sold. Like "HP per number of valves in the engine" or "600lbft V8 equivalent (yours is only an I3 though so just 120lbft)".
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Murloc - Saturday, February 23, 2019 - link
tbh people I've heard who have this sort of recharging needs during camping usually have a diesel generator.Destoya - Saturday, February 23, 2019 - link
There's obviously quite a difference in scale between a 5kg battery bank and a diesel generator. Something like this could easily fit into a backpack and could be quite useful for a small photography/drone team for instance. Enough power for cameras and small electronics when you're away from roads.vFunct - Saturday, February 23, 2019 - link
You can get small lead-acid battery+inverter combos at Walmart for cheap. They're heavy, but they're still small and can be carried by hand.sleepeeg3 - Saturday, February 23, 2019 - link
A lead acid battery with 73lbs and can be transported by your car. This weighs 12lbs.I do think this is going to fit an extremely niche market. Where are you going to go away from an outlet that requires you to charge your phone
47 times? If you're out backpacking in the wilderness and you've already used 12lbs of weight for this thing, you don't have enough food for 47 days.
I guess it makes sense if you want to get some drone footage on your backpacking trip or need a laptop / satellite phone for some government survey.
Either way, send like you would be better off with wise and financially by buying multiple chargers and distributing then between several people than this $700 monstrosity.
qap - Saturday, February 23, 2019 - link
I dont know where you came up with 73 lbs. 100Wh (12V, 9Ah) lead-acid battery has cca 5 lbs. You would need 4-5 of those + inverter. That makes around 25-30lbs. Definitely not 73.This battery pack is definitely not for backpacking - it is way too heavy. Even considering its capacity it is too heavy (only 85Wh/kg, Li-ion batteries have around 250Wh/kg so the whole pack should have above 150Wh/kg).
Pneumothorax - Saturday, February 23, 2019 - link
The problem with lead acid batteries is that in higher drain instances like charging laptops, the true total capacity is not going to be 9Ah. While li-ion batteries do well if discharged to 20% all the time, lead acid will quickly wear out if discharged to 20% frequently!vFunct - Saturday, February 23, 2019 - link
Or a lead-acid car-battery and inverter. You can get these for $100 at Wal Mart.vFunct - Saturday, February 23, 2019 - link
And the Wal-Mart packs can jump-start a car as well.mckirkus - Sunday, February 24, 2019 - link
Car batteries are not designed to be completely discharged and recharged. They're meant to start your car then get topped off by the alternator. But yeah, you can get a deep cycle SLA battery instead, and probably cheaper.SeannyB - Saturday, February 23, 2019 - link
Anker has something similar to this, and one prominent use case that I can recall was for CPAP users.Death666Angel - Saturday, February 23, 2019 - link
What does CPAP refer to? Google says "Continuous positive airway pressure" which refers to sleep therapy. Pretty sure that's not related to what you mean. :Dnevcairiel - Saturday, February 23, 2019 - link
I could see that, if you're camping and still want to sleep properly, need power from somewhere.cfenton - Saturday, February 23, 2019 - link
CPAP machines help with sleep apnea, which can be very serious for some people. Having a device that can run a CPAP machine if the power goes out is important, especially if you live in an area where power outages are frequent. Devices like this are far easier to keep ready and use than a generator.Death666Angel - Saturday, February 23, 2019 - link
I wouldn't trust my health on something advertised on a tech site though. Too many things can go wrong with consumer grade electronics.zepi - Saturday, February 23, 2019 - link
And what if you couldn’t afford fancy medical device, because your health insurance wouldn’t cover it or you live in a 3rd world country? Better live without one at all?mkaibear - Saturday, February 23, 2019 - link
Yep, and definitely what he meant too.This would be extremely useful for my CPAP machine.
norazi - Sunday, February 24, 2019 - link
Thats what he means... CPAP is a machine that help people with sleep apnea breath noramlly while sleeping. It looks like an oxygen mask hooked up to your face and obviously needs to have a VERY RELIABLE source of power. Thus the niche case use for this is for CPAP machine users as a backup incase of a power outage. A typical APC desktop UPS will only provide power for about an hour while this would run all night.DanNeely - Saturday, February 23, 2019 - link
That seems to be missing a pair of alligator clamps to jump start a car...Samus - Saturday, February 23, 2019 - link
I was thinking the same thing. Shame it doesn't support jumpstarting. It's also unfortunate it doesn't seem to have any sort of water resistance rating, basically eliminating it from being safely used outdoors, especially if camping.Opencg - Saturday, February 23, 2019 - link
300w x3 does not come close to the 5000w or more that you would need to jump a car. the battery may not support that level of output.Samus - Sunday, February 24, 2019 - link
Opencg. Wattage has nothing to do with it.I've jump-started a car off my R/C shortcourse truck battery. It's a cheap $25 5000mah 11.1v nominal (peak is well above the 12v necessary to crank a starter motor) and it's the size of a pack of cigarettes. The catch is it is rated at 50C; it can output 50x its rated capacity in a burst. Even cheap LiPo packs are rated at 25C which supplies the 125amps to jump-start a car on a mildly dead battery. These packs usually charge at 5C but good packs can charge at 10C (which means they can recharge in a few minutes from a capable charger.)
You need to understand the underlying chemistry used here. Lithium Ion, Polymer and even tiny LiFE cells can all jump-start a vehicle as is if they have the required discharge rating.
That said, even if they didn't want to use capable quality cells (which they SHOULD for $700!) they could use an amplifier in the form of a super capacitor or a separate low amp trio of lithium cells to supply the necessary current to turn over an engine. I think this is a very useful feature, especially for a device like this.
Ashinjuka - Saturday, February 23, 2019 - link
Always good to see LRF support on these types of devices.close - Saturday, February 23, 2019 - link
"The ChargeTech PS120K packs multiple batteries for a total capacity of 124,800 mAh (462 Wh), which is enough to charge a typical 13.3-inch laptop for 10 times, or Apple’s iPhone XR 47 times"Back of the napkin math doesn't really apply well. Not only will the 124800mAh pack only charge the 2942mAh iPhone XR battery just 42.5 time but also the battery capacity is lower the higher the discharge current. And lithium batteries are notoriously bad at this. You can easily lose 20-25% of the capacity just by increasing the discharge current.
The C value (Capability, the higher it is, the more current you can draw without significantly lowering its capacity) is much better for a lead acid battery, at the downside of about twice the weight.
So for people taking it to charge their phone 45 times it may work better than for those who assume they can power a lot of devices at the same time using the same math. This should be good to know for people to properly adjust their expectation to the use case.
Death666Angel - Saturday, February 23, 2019 - link
Huh? That's not how the C rate works. C is the capacity of the battery (any battery type). With most batteries, it is advisable to not charge them at a current larger than 1 C, for longevity sake. It is also advisable to not discharge them at unreasonable C rates. Many new lithium batteries are designed for certain tasks (car starter battery, drone flying) where high C-rate discharge is important, so they come with 30C, 50C, 100C ratings. Some people also don't want to wait a long time to recharge their battery, so they are fine at charging at 5C for a reduced cycle life. If a 50C batteries get discharged in a drone and lands when the drone indicates it only has 3.1V left (3.0V is generally the level at which you want to stop draining your lithium battery, non-standard chemistry not withstanding), it can easily get back up to 3.7V when you apply a simple 500mA discharge current to charge your phone (let's say this is a 5000mAh battery, so a 0.1C discharge rate). But try using it for a 10C application it won't let you until you recharge it again (the voltage will collapse immediately).Lead acid batteries are just as general as lithium ones. You have car batteries which have huge amperage (C-rate in your example), but really bad deep discharge functionality. And then you have ones that are used in UPSes that offer fine discharge rates (less than car batteries) but great deep cycle stability. It's not at all how you describe it, unfortunately.
This is why capacitors are the future of electric mobility, not batteries. But that's beside the point. :D
close - Sunday, February 24, 2019 - link
I thought I was pretty clear about what I meant. Let's keep it simple this time: a battery will have lower capacity the faster you discharge it (the higher the C rate, the lower the energy and capacity). I'm not talking about exceeding load limits. I'll let the experts speak now:https://www.panasonic-eneloop.eu/en/capacity-not-c...
"The available capacity of a battery depends upon the rate at which it is discharged."
"A battery rated at 100 Ah will deliver 5 A over a 20 hour period at room temperature. However, if it is instead discharged at 50 A, it will run out of charge before the theoretically-expected 2 hours."
I tested this myself with my regular RAV Power and Anker powerbanks (all under ~30000mAh) although I didn't really need to validate physics. The capacity was 10% lower with 2.4A vs. 1A discharge. And this is while starting with ~65-75% usable capacity anyway. It appears that the increase in temperature and thus in voltage does not compensate for the increase in resistance.
Since the battery in the article is obviously meant for heavy duty use, not charging one phone, these figures would have been relevant. I'm willing to bet this doesn't actually go over 100000mAh and will be less than that when discharging it rapidly (perhaps no more than 80000mAh).
Sonic01 - Saturday, February 23, 2019 - link
meh, i built my own 600wh battery yesterday for £40, using some recycled broken laptop batteries. took 3.5h to build. $700 for one sounds crazy after that XDpiroroadkill - Saturday, February 23, 2019 - link
The advertising picture notes "MAH", which would clearly mean mega-amp hours, not milli-amp hours. SI prefixes are very case sensitive. Also, this whole amp-hour marketing makes no sense, because it's based on a voltage of 3.7. We need to get away from it. Way away from it. Wh is what we need, at least.Death666Angel - Saturday, February 23, 2019 - link
All it does is save you one multiplication. And I'm sure some Chinese vendors will fuck that up again as well.mkozakewich - Sunday, February 24, 2019 - link
No, if we're using mAh then people really want the numbers to be comparable. I've already seen a tablet with a 7.4v battery double its mAh to make a "3.7v equivalent" number. If they were using watt-hours, they wouldn't have had to do anything special.Especially considering this kind of equipment: Usually we use 12v car batteries to make portable power sources with inverters, and this box has the same 400-500 Wh despite the huge mAh number.
yannigr2 - Saturday, February 23, 2019 - link
Why not use a much cheaper,or two, UPS?Barkuti - Monday, February 25, 2019 - link
13S3P internal battery made with 3200mAh rated cells, probably LG INR18650-MH1, Panasonic NCR18650BM or Samsung INR18650-32A, or maybe some other higher capacity cells if the fellow ChargeTech designers are rigorously honest and like to err on the safeside as cell typical ratings usually are about best case scenarios.Actual internal battery capacity thus should be 3200mAh × 3 = 9600mAh, for a 3.7V × 13 = 48.1V or ≈48V nominal figure. This fits well with the likely being used 48V AC inverter.
124800mAh marketing gimmick. Capacity means really nothing here, like torque or rpm when talking about motors. Capacity times voltage is energy, 462Wh 0.2C typical in this case, which by the way you won't see at the outputs because of DC/DC and DC/AC conversion losses.
close - Thursday, February 28, 2019 - link
"like torque or rpm"You'd be right if engine manufacturers would use gimmicks like stating numbers that are relative to some "reference" engine or component, not the actual one being sold. Like "HP per number of valves in the engine" or "600lbft V8 equivalent (yours is only an I3 though so just 120lbft)".